Bl rant

[mr crab]

This is very informational

https://lacoast.gov/reports/static/HILCP_3.pdf

[mr crab]

Originally Posted by mr crab

This is very informational

https://lacoast.gov/reports/static/HILCP_3.pdf

its from 1997, but still very comprehensive. I found a lot of answers to questions asked here within this report. It certainly explains the differences between B.L. and Sabine....truly apples and oranges hydrlogicaly spreaking.

[Duck Butter]

Originally Posted by mr crab

its from 1997, but still very comprehensive. I found a lot of answers to questions asked here within this report. It certainly explains the differences between B.L. and Sabine....truly apples and oranges hydrlogicaly spreaking.

good read, the 3rd paragraph really tells the story of why weirs are needed:

Finally, in 1968 the ship channel was substantially widened again to
400 ft and dredged to its current depth of 40 ft (Figure 27; Waldon 1996). Prior to the initial dredging of the CSC, there was a 3.5-ft-deep shoal at the mouth of the Calcasieu River (War Department 1897). This natural bar acted as a constriction, minimizing saltwater and tidal
inflow into the basin. Removal of the channel mouth bar, coupled with subsequent widening and deepening of the CSC, allowed increased saltwater and tidal intrusion into the estuary, resulting in catastrophic marsh loss, tidal export of vast quantities of organic marsh substrate,
and an overall shift to more saline habitats in the region (USDA 1994). In addition, the CSC permits the upriver flow of denser, more saline water as a saltwater wedge. In 1968, the USACE completed construction of the Calcasieu River Saltwater Barrier on the Calcasieu River north of the city of Lake Charles. This barrier minimized the flow of the saltwater
wedge into the upper reaches of the Calcasieu River to protect agricultural water supplies.

[Duck Butter]

Death of the Saw Grass Marsh in the Chenier Plain

Very little biological documentation exists of Chenier Plain habitats prior to the
1930s. However, abundant evidence indicates that the area was substantially fresher thenthan now. Both O’Neil (1949) and a 1951 Soil Conservation Service vegetative type map of Cameron Parish show broad expanses of unbroken saw grass (Cladium jamaicense) marsh (USDA 1951; Figure 30). Saw grass is found in fresh and intermediate marshes and tolerates salinities between 0 and 2 ppt (Penfound and Hathaway 1938). At the time of the 1951survey, saw grass marsh covered approximately 475 mi of Cameron Parish and was the dominant vegetative community. Additional evidence that the Chenier Plain was historically much fresher than it is now includes the following:

2
• Cypress trees (Taxodium distichum), with a salinity tolerance of 2 ppt (Chabreck 1972), lined Black Bayou as recently as the 1930s. This is significant because vegetative type maps of 1949, 1968, 1978, and 1988 indicate that much of Black Bayou meandered through brackish marsh, which, due to elevated salinities, could no longer support cypress tree growth (O’Neil 1949; Chabreck et al. 1968; Chabreck and Linscombe 1978, 1988).

• Water from Calcasieu Lake was fresh enough to be used in the irrigation of rice fields in Cameron Parish around 1875-1910 (David Richard, Stream Companies, Inc., personal communication). Water from Calcasieu Lake must have been essentially fresh during this period, because rice is adversely affected by water salinities that exceed 0.6 ppt (Hill 2001).

• In the early 1900s, lower Calcasieu Lake was considered marginal habitat for oysters (Crassostrea virginica) because of the frequency of freshwater and low-salinity events there. Oysters, which inhabit waters within the salinity range of 5-30 ppt (Galtsoff 1964), are now found throughout much of the Calcasieu Lake bottom (USDA 1994).

In contrast to these formerly fresh conditions in Calcasieu Lake, average salinities at fiveCameron Prairie Refuge monitoring stations within Calcasieu Lake ranged from 8.01 to 11.66 ppt during 1994-95. The CSC is undoubtedly the major cause of increased salinity in the Calcasieu Basin.

[Duck Butter]

Area 19 (South end of the Big Lake Mapping Unit):
East-west canals were cut by North American Land Company steam dredges prior to1900, which resulted in breaching of the Calcasieu Lake rim. This area was farmedfor rice; freshwater from inside Calcasieu Lake was used to irrigate rice fields fromaround 1875 until 1910. Saltwater and tidal invasion (salinities up to 30 ppt)associated with the deepening of the CSC in the 1940s, coupled with the loss offreshwater inflow from the Pleistocene terrace due to construction of the GIWW, contributed to marsh loss.

Area 20 (Sweet/Willow Lakes Unit):
This area was a solid marsh until marsh buggies were used in the 1950s to mash down the marsh to create duck ponds. Around 1925-28, the levee encompassing the brinepit in Area 20A broke and saltwater from the brine pit killed much of this freshmarsh. The use of brine pits and the pumping of produced water into adjacentmarshes were abandoned in this area in 1948 when injection wells began to be usedfor brine disposal. There are still about 45 producing oil wells in this area. Erosion of the north bank of the GIWW has resulted in a direct hydrologic connection with both Willow Lake and Sweet Lake. The CWPPRA Sweet Lake/Willow LakeShore Protection Project is addressing this problem. The Coast 2050 Region 4 Regional Planning Team indicated that land loss in this area was due to altered hydrology, flooding, and storms (LCWCRTF/WRCA 1998).

Area 20A (Sweet/Willow Lakes Unit: Section 36):
This area was owned by North American Land and Sweet Lake Land & Oil and leased to Union Oil Company of California at the turn of the century. It was utilizedas a produced-water disposal pit for the oil withdrawn from the Sweet Lake Unit inthe 1920s. It is now about 4 ft deep because of levee deterioration.

Area 21 (Cameron-Creole Watershed Unit):
Loss of the historical saw grass marsh in this area is attributable to saltwater intrusionfrom the CSC in the 1950s. The whole area began dying after cuts were madethrough the Calcasieu River channel mouth bar in the late 1930s and early 1940s. Marsh deterioration occurred through progressive dying of the standing saw grass. When Hurricane Audrey hit in 1957, the saw grass system was alreadydead or dying, and the hurricane’s storm surge cleared away the dead and deteriorated saw grassstands. Much of the saw grass was killed by the discharge of produced water fromlocalized oil wells.
Area 22 (Cameron-Creole Watershed Unit): Saltwater intrusion from the Creole Canal and Calcasieu Lake through the CalcasieuShip Channel killed some of the marsh vegetation, and tidal action eroded the highlyorganic soils in this area.

These findings reveal that, in most areas, a combination of human-induced hydrologic changes, sometimes accompanied by severe storm events, has resulted in virtually all of the habitat changes and land losses in the Calcasieu-Sabine Basin. The hydrologic alteration that has had the most impact is the CSC, a major avenue for saltwater and tidal intrusion, which has caused extremely severe marsh losses. Secondary causes of landscape change include oil- and gas-related activities such as canal construction, incidentalimpoundment, and produced-water discharge; historical natural resource managementpractices that are nolonger employed; agriculture through intentional impoundment of the marsh for wildlife management and cattle grazing; and nutria herbivory and trapping canal

[Smalls]

Originally Posted by mr crab

This is very informational

https://lacoast.gov/reports/static/HILCP_3.pdf

Man, I'm glad someone could find that link. I talked with the people that manage that site and got them to put it up. A year or two ago, you couldn't find the whole report. I needed it for my research, and luckily they were able to put it all back up.

Definitely a good read. I wanted to post this aa few weeks ago, but couldn't find it. All I have is the PDF, which is way too big to post here.

This is the stuff I've been preaching for over a year now.